Rumetrace Magnesium Capsules

Rumetrace Magnesium Capsules

Contains 210g magnesium alloy (189g magnesium) for cattle.


  • Capsule form administered to individual cattle
  • Longest lasting form of Magnesium supplementation available for NZ cattle
  • Sustained Mg release for 9 - 12 weeks
  • Releases Mg exponentially at 1.5% per day
  • Research validates consistent release over time
  • New research with two capsules per animal
  • Rumetrace brand exclusive to vets
  • Available in cartons of 40 capsules, capsules sold individually by vet wholesalers


  • Dose surety for every animal treated
  • Provides a solution for supplementing Mg when daily pasture dosing or water trough treatment is impractical on farm; reducing risk of animal mortality

  • Avoids having to supplement magnesium on a daily basis

  • Magnesium availability to the cow is not dependant on feed and water availability/intake
  • Cattle can also be treated with two capsules, doubling daily Mg release to 4 grams per day

  • AgriHealth technical advice and support available to NZ farmers and rural vets
  • Easy to store and dispense correct quantity for all herd sizes


Capsule comprised of two semi-cylindrical magnesium alloy castings hinged together along one side by a rubber moulding.

Pack Sizes

Available in cartons of 40 capsules
Rumetrace applicators available separately


On entering the reticulo-rumen, the folded cylinder springs open to prevent regurgitation. The conductive particles of the rubber hinge act as a cathode, and the magnesium alloy semi-cylindrical components act as anodes which erode slowly by electrolysis to release magnesium at a constant rate of 1.5% of weight per day . The erosion occurs continuously over a period of 9 - 12 weeks (refer Rumetrace Flyer for release graph over time). The magnesium is released in a form (Mg++) that can be immediately absorbed into the bloodstream.


A sustained-release magnesium capsule to aid in the prevention of grass staggers (hypomagnesaemia) in cattle, particularly during the high-risk period associated with calving and lactation in the spring.  Aids in the prevention of grass staggers for 9 - 12 weeks.


Administer 1 capsule per animal 7 - 10 days before the grass staggers risk period begins or 7 - 10 days prior to calving. Administer using the Rumetrace Magnesium capsule applicator.
Note if administering to cows in the face of a grass staggers (hypomagnesaemia) outbreak, also administer another Mg supplement (eg MgO) to cows for 7 - 8 days as sufficient Rumetrace Mg release via electrolysis may not commence immediately.

Withholding times


Special Precautions

Do not use excessive force during administration. Wait until the animal swallows to progress the capsule applicator over the back of the tongue and down the throat. Do not dose bellowing cattle.


Store below 30°C in a dry place.
Restricted Veterinary Medicine, ACVM Registration Number A10958